Message from one scene to another (not an overlay)
I've done some tests and you can not send a message to a scene that did not loaded.

In the example 1 the scene1 send a message when mouseOver the scene2 recive the message and add  1 to count, i use a script to print the value.

Scene 1 logic:



Scene 2 logic:

from bge import logic

obj = logic.getCurrentScene().objects['Suzanne']
print(obj['count'])




Behaviour when:

scene2 IS NOT an overlay nor background



scene2 IS overlay or background



In the example 2 i dont use any message. I store the value in an attribute of bge.logic module.

Scene 1 logic:

from bge import logic

if not hasattr(logic, 'count'):
    logic.count = 0
else:
    logic.count += 1




Scene 2 logic:

from bge import logic

if hasattr(logic, 'count'):
    print(logic.count)




Behaviour when:

scene2 IS NOT an overlay nor background